@NogDogMar 04.2010 — #Not sure what you mean by "realm", but you might want to try the following to see if what you are looking for is in the $_SERVER array:
@Jarrod1937Mar 04.2010 — #If its just for development checkout "live http headers", a nice plugin for firefox. It will show the entire http request and response conversation.
If you're actually printing something from the header onto the screen for users (which would be odd) the $_SERVER array probably has what you need.